Cross-country ski-boots in which the fastening axis, which provides for connection with the binding borne by the ski, is unitary with an anchoring element extending rearward horizontally or substantially horizontally within the front portion of the sole, are already well known. A device of this kind is described, for example, in patent application No. EP-0 169 429. Because this anchoring element extends over a significant length within the front portion of the sole, the anchoring element gives additional rigidity to this front portion. This arrangement constitutes a major disadvantage, since the cross-country ski boot must provide a certain flexibility to the front end of its sole, so as to allow the boot to be raised and lowered successively during cross-country skiing.